Drs. Levey, Dwyer, Perrone and the clinical staff at NEMC are participating in Phases I and II of the MDRD study. The specific aim of this application is for the same personnel at the sane institution to continue their participation in Phases III and IV. The goals of Phases I-II were to develop protocols, forms, operations manuals and organizational structures, to conduct a limited pilot study, and to assess the feasibility of a full scale trial. Investigators and clinical staff at NEMC have achieved these goals: Drs. Levey, Dwyer, and Perrone have key leadership roles on the steering and planning committee, including membership on the Executive Committee and chairmanships of the Patient Selection, Renal Function, Nutrition Advisory, GFR Study, and Protocol Review committees. They have cooperated with NIH, HCPA, and the Data Coordinating Center in fulfillment of the terms of the Cooperative Agreement. They have organized a MDRD Clinic with full supporting services from NEMC, met the recruitment goal for Studies A and B, randomized all eligible patients and provided timely, accurate, and complete data. They have completed the GFR Study (Methods and Markers for Measurement of GFR), presented the results at the 1986 Meeting of the American Society of Nephrology, and developed and received approval to conduct an ancillary study (Additional Measures of Nutritional Status and Safety). The goals of Phases III-IV are to enroll 40 patients into Studies A and B within 21 months, provide long term follow up data, and participate with the Data Coordinating Center in preparing interim and final reports on study outcomes. Personnel are able to achieve these goals at NEMC: They have expertise in multicenter clinical trials, are experienced in MDRD procedures, are "in place" and ready to begin work on Phase III, and are committed to long term collaboration with NIH, HCFA and other centers. The facilities at NEMC, particularly the Nephrology Clinic, Frances Stern Nutrition Center and the recent commitment of additional space and resources for the development of a Nephrology Clinical Research Center under Dr. Levey's direction, provide an ideal environment for the conduct of this study. The formation of a Metropolitan Boston MDRD Recruitment Center to be operated jointly by all MDRD clinical centers in Boston is a highly efficient and effective strategy which assures that NEMC will meet the recruitment goal for Phase III.